EF 135 F/2L USM temptation

I used to have the EF 70-200 f/2.8L USM, but due to the weight and size I sold it and bought EF 70-200 f/4L IS USM. I have never regretted the swap, but it's true, it hasn't so nice bokeh. Buying 70-200 f/2.8L IS USM II wouldn't solve my problem because of reasons mentioned above. That is why I would prefer for portrait work 135 f/2 prior to 70-200 f/4L IS USM and the question is if the money is worth one stop and 1/3 of focal length as I already have the macro 100 f/2.8 USM.